Strange banding etc.

Good morning... So i decided i had some downtime on my taz 5 so i thought id print a vase for fun.
Its clear PETG

What i noticed while it was printing was a very odd sound coming from the extruder assembly.
http://i1132.photobucket.com/albums/...psoptkugix.mp4
The audio/video is here.. It only happens on certain movements, but doesnt seem to be limited to the X or Y


Also, im seeing a clear band for a few layers every 50 layers or so in my print. then the normal style banding re appears.
http://i1132.photobucket.com/albums/...psamcm0gob.jpg
http://i1132.photobucket.com/albums/...psjtffu2hc.jpg

This is a brand new printer, less than 20 hours on it. Im not sure what else to tweak on it. First layers are perfect.

thanks

Is this happening on all of your prints? Was this vase printed with the "Spiralize Contour" option?

That sound sounds like the stepper motors are actually making those fine movements which is giving you that wave effect. Is the object designed smooth? What slicer are you using?